Number 1 are given the vector. It is necessary: ​​a) to calculate the mixed product of three vectors; b) find the module of the vector product; c) calculate the scalar product of two vectors; d) check whether two vectors are collinear or orthogonal; e) check whether three vectors will be coplanar: a (-4; 3; -7); b (4; 6; -2); c (6; 9; -3).

No. 2 The vertices of the pyramid are located at points A (7; 4; 9); B (1; –2; –3); C (–5; –3; 0); D (1; –3; 4)

No. 3 Force F (2; 2; 9) is applied to point A (4; 2; –3). Calculate a) the work of force F in the case; when is the point of her application; moving in a straight line; moves to point B (2; 4; 0); b) the modulus of the moment of force F relative to point B.